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By 2030, solid–state LED lighting is predicted to replace current incandescent lighting, saving the US alone 395 TWh, an amount of electricity currently worth $40 billion. White LED lighting is dependent on the down-conversion of a portion of the blue light created in an InGaAs LED into the yellow spectrum to create white light. This is done by electron excitation and subsequent relaxation in a rare earth element (namely Ce3+ of Eu2+), which is doped in small percentages on a phosphor lattice. Previous work has shown that the Debye temperature, which is a measure of resistance to phonon modes in a lattice, can be used as a proxy to predict high efficiency phosphor host compounds . Additionally, it is hypothesized that high Debye temperature is correlated with good thermal stability, a crucial parameter in the next generation of lighting using lasers. The present work aims to utilise both conventional solid–state and rapid microwave–assisted heating techniques to prepare high Debye temperature phosphor host lattices. X-ray diffraction is leveraged to elucidate phase information and guide processing procedures, the excitation and emission properties of the phosphors is characterised, and the efficiency (i.e., photoluminescence quantum yield) of these new phosphors is measured and calculated. The goal of the current work is to prepare high efficiency phosphors suitable for use in solid–state laser–based lighting.
1. J. Brgoch, S. P. DenBaars, and R. Seshadri, Proxies from Ab-initio calculations for screening efficient Ce3+ phosphor hosts, J. Phys. Chem. C 117 (2013) 17955–17959.